Ok, I have a Christian teen website and am updating it. I want to put a fire effect on it because, as Christians, we should be on fire for God. I want something to like go around an image or as a background, something that makes something look like it's burning or on fire.

If you have PSP, there is a set of filters called Eye Candy, and it has a fire effect. That sounds like what you are looking for.
Also, you could probably use the lasso tool to cut out the image, and paste it as a new layer "on top" of an image of fire.